JPH11245154A - Manufacture of wire saw - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manufacture a wire saw at a high speed by bonding a synthetic resin and abrasive grains to a wire core material with the electrodepositon method, and heating and treating them so as to fix the abrasive grains with the synthetic resin. SOLUTION: A wire core material 1 is driven for traveling by rotating pulleys 2, 3. An electrodepositon tank 4 filled with the water base paint including the mixture of the synthetic resin and the abrasive grains, and the synthetic resin and the abrasive grains are adhered to the wire core material 1 in electrodepositon tank 4. The wire core material 1, to which the synthetic resin and the abrasive grains are adhered in the electrodepositon tank 4, is fed to a first washing vessel 5, a second washing vessel 6 and a third washing vessel 7 in order, and a surface thereof is washed. The washed wire core material 1 is fed to a heating furnace 8, and heated and treated so as to dry the water base paint, and the synthetic resin is hardened and strongly secured the abrasive grains, and the surface of the wire core material 1 is formed with an abrasive grain layer so as to form a wire saw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a wire saw. More specifically, when the present invention is used for cutting a brittle material such as a silicon ingot, a large tension can be applied, the number of disconnections is small, the loss of the material due to the cutting margin is small, the finish of the cut surface is good, Moreover, the present invention relates to a method for manufacturing a wire saw that can be easily manufactured at high speed.

[0002]

2. Description of the Related Art A cutting wheel, an ID blade, and the like are used for slicing a brittle material such as a silicon ingot to cut out a silicon wafer for an LSI.
Band saws, wire saws and the like are used. When cutting material using such tools, the loss of material equivalent to the blade thickness of the tool is inevitable, so the thinning of wheels and blades has been promoted, and wire saws with small wire diameters have attracted attention. ing. Conventionally, as a wire saw for cutting a silicon ingot, a wire saw in which abrasive grains are fixed to the surface of a metal wire such as a piano wire or a tungsten wire by metal plating has been used. However, it takes a long time to fix the abrasive grains by metal plating, and a large-scale apparatus is required to plate a large number of core materials.
It is not easy to manufacture economically, especially 1000m
It was difficult to manufacture the above long wire saw. Further, when a wire saw to which abrasive grains are fixed by metal plating is used, there is a tendency that a cut surface is rough and a good finished surface is hardly obtained. Further, there is a problem that the wire saw is likely to be broken in a reel having a small curvature due to metal fatigue of the plated metal. Japanese Patent Application Laid-Open No. 8-126953 proposes a wire saw in which abrasive grains are dispersed and fixed to a core wire of polyethylene, nylon, polyester or the like via a synthetic resin adhesive. Using this wire saw, it is said that the residual processing distortion after cutting such as silicon ingot is small and high quality products can be obtained stably, but the core wire of polyethylene, nylon, polyester etc. is compared with metal wire. Since both the tensile strength and the elastic modulus were low, the tension applied to the wire saw at the time of cutting was limited, and the wire saw often broke. In addition, it is difficult to uniformly bond the abrasive grains and the synthetic resin to the core material, and further, it is difficult to obtain roundness about the axis of the core wire, and the abrasive grain layer is biased or the thickness is different. There was a problem. For this reason, there has been a demand for a method of manufacturing a wire saw that can be easily manufactured, can apply a large tension at the time of cutting, has few disconnections, and has a good cut surface finish.

[0003]

When the present invention is used for cutting a brittle material such as a silicon ingot, a large tension can be applied, the disconnection is small, the material loss due to the cutting margin is small, and the cut surface can be cut. An object of the present invention is to provide a method for manufacturing a wire saw that has a good finish and can be easily manufactured at high speed.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have made a synthetic resin and abrasive grains adhere to a wire core material by an electrodeposition coating method and heat-treated. By fixing the abrasive grains with a synthetic resin, the wire saw can be easily manufactured at high speed.Furthermore, when the brittle material is cut using this wire saw, there is little disconnection during the work and the finish of the cut surface is good. The inventors have found that the present invention has been completed, and based on this finding, have completed the present invention. That is, the present invention provides (1) a method for manufacturing a wire saw, which comprises applying a synthetic resin and abrasive grains to a wire core material by an electrodeposition coating method and then performing a heat treatment; The method for manufacturing a wire saw according to the item (1), wherein the plurality of wire cores travel on the pulleys or the multi-groove pulleys, and the synthetic resin and abrasive grains are attached to the plurality of traveling wire cores.
And (3) the abrasive grain has a particle size of 50 μm or less, and the outermost diameter of the wire saw is 120 to 500 μm.
(2) A method for manufacturing a wire saw according to the item (2).

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for manufacturing a wire saw of the present invention, a synthetic resin and abrasive grains are adhered to a wire core material by an electrodeposition coating method, and then heated to fix the abrasive grains with the synthetic resin. An abrasive layer is formed on the surface of the core material.
In the method of the present invention, as the synthetic resin, a known synthetic resin used for an electrodeposition coating method can be used without particular limitation. That is, in the anionic electrodeposition coating method, for example, it is possible to use an anionic resin or the like that imparts water affinity by neutralizing a carboxyl group of an acrylic resin or the like with an organic amine, ammonia, potassium hydroxide, or the like. it can. In the cationic electrodeposition coating method, the amino group of the amino acrylic resin or the like is neutralized with an organic acid such as acetic acid or lactic acid, or an onium salt such as a quaternary ammonium salt or a sulfonium salt is introduced. For example, a cationic resin imparted with water affinity can be used. In the method of the present invention, a filler or a lubricant can be added to the synthetic resin as required. Examples of the filler to be blended include non-conductive fillers such as carborundum, silica powder, antimony trioxide, clay, mica, alumina, and silica. Examples of the lubricant to be blended include molybdenum disulfide and graphite. The abrasive used in the method of the present invention is not particularly limited. Examples thereof include superabrasives such as diamond abrasives and cBN abrasives, powders obtained by grinding basalt, granite, tuff, and the like, cerium oxide, sapphire, ruby, and garnet. And general abrasive grains such as silicon carbide and aluminum oxide. Among them, diamond abrasive grains and cBN abrasive grains can be used particularly preferably because they can cut brittle materials such as silicon ingots efficiently and sharply. The wire core material used in the method of the present invention is not particularly limited as long as it is a material having conductivity, and examples thereof include a steel wire such as a piano wire and a metal wire such as a tungsten wire and a molybdenum wire.

In the method of the present invention, an electrodeposition coating method is used to attach the synthetic resin and the abrasive grains to the wire core material. There is no particular limitation on the method of attaching the synthetic resin and the abrasive grains to the wire core material by the electrodeposition coating method. For example, an aqueous paint containing the synthetic resin and the abrasive grains is prepared, and a single electrodeposition coating tank is used. Thus, the synthetic resin and the abrasive grains can be simultaneously attached to the wire core material. In the method of the present invention, since the synthetic resin and the abrasive grains are attached to the wire core material by the electrodeposition coating method, the synthetic resin and the abrasive grains have good throwing power, and uniformly adhere to the surface of the wire core material, An abrasive layer having a uniform thickness and abrasive distribution can be formed on the surface of the wire core material. In the method of the present invention, after attaching the synthetic resin and abrasive grains to the wire core material, by heating, the paint is dried and the synthetic resin is cured, and a synthetic resin film is formed on the surface of the wire core material, An abrasive grain layer to which the abrasive grains are fixed is formed. The heating conditions can be selected according to the characteristics of the synthetic resin used. Usually, after pre-drying at 60 to 120 ° C. for 5 to 20 minutes, baking is performed at 100 to 200 ° C. for 10 to 60 minutes. A granular layer can be formed.

FIG. 1 is an explanatory view of one embodiment of a method for manufacturing a wire saw according to the present invention. FIG. 1 (a) is a schematic side view, and FIG. 1 (b) shows a state in which one wire saw is manufactured. FIG. 1C is a schematic plan view showing a state in which ten wire saws are simultaneously manufactured. The wire core 1 runs by being driven by rotating pulleys 2 and 3. The wire core is an anode in the case of anionic electrodeposition coating, and is a cathode in the case of cationic electrodeposition coating. There is no particular limitation on the method of applying a potential to the wire core, but in this embodiment, the potential is applied to the wire core via the pulley 2 made of a conductor. In this embodiment, the electrodeposition coating tank 4 filled with an aqueous coating containing a mixture of a synthetic resin and abrasive grains.
The synthetic resin and abrasive grains adhere to the wire core material in the electrodeposition coating tank. In the case of anionic electrodeposition coating, the electrodeposition coating tank can be made of stainless steel, and the tank can be used as a cathode as it is. For cationic electrodeposition coating,
It is preferable that the electrodeposition coating tank is lined and an anode is separately provided. It is preferable that the electrodeposition coating tank stirs the aqueous paint in the tank, prevents sedimentation of the abrasive grains, and makes the liquid temperature uniform. In the electrodeposition coating tank, the wire core material to which the synthetic resin and the abrasive grains have adhered is then removed from the first washing tank 5 and the second washing tank.
The water is sequentially sent to the washing tank 6 and the third washing tank 7 to wash the surface. The washed wire core is then sent to a heating furnace 8 where it is heated to dry the water-based paint, the synthetic resin is hardened, and the abrasive grains are firmly fixed. A layer is formed to form a wire saw. The wire saw is wound by a winding device via a rotating pulley 3.

In the method of the present invention, a plurality of wire cores are run on a plurality of rotationally driven pulleys or multi-groove pulleys, and a synthetic resin and abrasive grains are applied to the running plurality of wire cores. After being adhered by a coating method, heat treatment can be performed. In the embodiment shown in FIG. 1C, ten wire cores 1 are driven by rotating multi-groove pulleys 9 and 10 to travel. The wire core is an anode in the case of anionic electrodeposition coating, and is a cathode in the case of cationic electrodeposition coating. Although there is no particular limitation on the method of applying a potential to the wire core, in the present embodiment, the potential is applied to the wire core via a multi-groove pulley 9 made of a conductor. Also in this embodiment, the electrodeposition coating tank 4 filled with an aqueous paint containing a mixture of a synthetic resin and abrasive grains is provided, and the synthetic resin and the abrasive grains adhere to ten wire cores in the electrodeposition coating tank. The ten wire cores to which the synthetic resin and the abrasive grains are attached are then separated into a first washing tank 5, a second washing tank 6, a third washing tank 7
And then the surface is cleaned. The washed wire core is then sent to a heating furnace 8 where it is heated to dry the water-based paint, the synthetic resin is hardened, and the abrasive grains are firmly fixed. A layer is formed to form a wire saw. The ten wire saws are wound by a winding device via a rotating multi-groove pulley 10. FIG. 2 is an explanatory view of one embodiment of a wire saw manufactured by the method of the present invention. FIG. 2 (a) is a schematic cross-sectional view of a wire saw having a large abrasive grain density, and FIG. 2 (b) is a schematic view thereof. FIG. 2C is a schematic cross-sectional view of a wire saw having a small abrasive grain density. The wire saw of the present embodiment is a single wire 1
1 is used as a core material, and a synthetic resin film 12 adheres abrasive grains 13 on its surface to form an abrasive layer. FIG. 3 is an explanatory view of another embodiment of the wire saw manufactured by the method of the present invention. FIG. 3 (a) is a schematic sectional view of a wire saw having a large abrasive grain density, and FIG. Target side view, Fig. 3 (c)
FIG. 1 is a schematic sectional view of a wire saw having a small abrasive grain density. In the wire saw of this embodiment, a stranded wire 14 is used as a core material, and a synthetic resin film 12 adheres abrasive grains 13 on a surface thereof to form an abrasive layer.

In the method of the present invention, the particle size of the abrasive used is preferably 50 μm or less. Abrasive grain size is 5
If the thickness exceeds 0 μm, the diameter of the obtained wire saw becomes large, the cutting margin when cutting the material increases, and the loss of the material may increase. The outermost diameter of the wire saw produced by the method of the present invention is preferably from 120 to 500 μm. If the outermost diameter of the wire saw is less than 120 μm, the strength of the wire saw may be insufficient. If the outermost diameter of the wire saw exceeds 500 μm, the margin when cutting the material increases, and the amount of material loss may increase. According to the manufacturing method of the wire saw of the present invention, since the abrasive grains are fixed to the surface of the wire core material with the synthetic resin, the processing speed is faster than the fixing of the abrasive grains by metal plating, and the length of 1,000 m or more is long. A wire saw can be easily manufactured in a short time. In addition, since the binder of the abrasive grains is a synthetic resin, when cutting a brittle material such as a silicon ingot, compared with a case where a wire saw in which the abrasive grains are fixed by metal plating such as nickel is used.
A cut surface with good finish is obtained. Wire saws with abrasive grains fixed by metal plating are prone to breakage due to metal fatigue of the plated metal when used for a long time, but wire saws manufactured by the method of the present invention use a synthetic resin as a binder, There is little risk of disconnection due to fatigue of the binder. In the method of the present invention, since the synthetic resin is attached to the wire core by an electrodeposition coating method together with the abrasive grains, compared with the resin immersion method, the synthetic resin and the abrasive grains have a uniform thickness on the surface of the wire core material, Moreover, it can be attached at a high speed. In addition, the synthetic resin uniformly adheres to the abrasive grains and the wire core material, and has strong adhesion. Furthermore, since a large number of wire cores can be run in parallel, and the synthetic resin and abrasive grains can be simultaneously attached to a large number of wire cores and subjected to heat treatment, a wire saw can be manufactured with high productivity. Can be. The wire saw manufactured by the method of the present invention is
Since the roundness is good and the variation in the outer diameter is small, a cut surface excellent in flatness can be obtained when used for cutting a silicon ingot.

[0010]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the present invention. Example 1 A wire saw was manufactured using a piano wire having a diameter of 0.2 mm as a core material. Diamond abrasive grains having a particle diameter of 30 to 40 μm were used as abrasive grains, and an anionic electrodeposition paint [Shimizu Co., Ltd., Elecoat AM-1, solid content 10% by weight] was used as a paint. 6 parts by weight of diamond abrasive grains were added to 100 parts by weight of the anion-type electrodeposition coating material, and the mixture was placed in a SUS304 electrodeposition coating tank, and the coating temperature was controlled at 25 ° C. The piano wire is used as the anode and the electrodeposition tank is used as the cathode.
A piano wire was run so that a potential difference of 00 V was applied and the immersion time in the electrodeposition coating tank was 2 minutes. Synthetic resin and abrasive grains uniformly adhered to the surface of the piano wire. The piano wire to which the synthetic resin and the abrasive grains were adhered was sequentially washed with water in three washing tanks, then sent to a heating furnace, and heated at 180 ° C. for 30 minutes to dry the electrodeposition paint and harden the synthetic resin. A wire saw having an average outermost diameter of 284 μm in which a uniform abrasive layer having an average thickness of 42 μm was formed on the surface of the piano wire was obtained. Using this wire saw, peripheral speed 120m / min
Reciprocating a wire saw having a total length of 20 m, a silicon ingot having a diameter of 6 inches, and a pressing load of 400 g;
Cutting was performed using water as a cutting fluid under the condition of a wire tension of 3.5 kgf. The time required for cutting was 5.0 hours for the first sheet,
The first sheet was 5.8 hours, the third sheet was 6.3 hours, and the fourth sheet was 6.6 hours. Example 2 A wire saw was manufactured using a piano wire having a diameter of 0.18 mm as a core material. Diamond abrasive grains having a particle diameter of 20 to 30 μm were used as the abrasive grains, and a cationic electrodeposition paint [Shimizu Co., Ltd., Elecoat CM, solid content 10% by weight] was used as the paint. 6 parts by weight of diamond abrasive grains were added to 100 parts by weight of the cationic electrodeposition coating material, and the coating material was lined with a PVC resin and placed in an electrodeposition coating tank equipped with a carbon electrode.
C. was controlled. A piano wire was used as a cathode, a carbon electrode was used as an anode, and a potential difference of 100 V was applied between the two to run the piano wire so that the immersion time in the electrodeposition coating tank was 1.5 minutes. Synthetic resin and abrasive grains uniformly adhered to the surface of the piano wire. The piano wire to which the synthetic resin and the abrasive grains were adhered was sequentially washed with water in three washing tanks, then sent to a heating furnace, and heated at 180 ° C. for 30 minutes to dry the electrodeposition paint and harden the synthetic resin. A wire saw having an average outermost diameter of 244 μm in which a uniform abrasive layer having an average thickness of 32 μm was formed on the surface of the piano wire was obtained. Using this wire saw, a silicon ingot having a diameter of 6 inches was cut in the same manner as in Example 1. The time required for cutting was 6.1 hours for the first sheet, 6.4 hours for the second sheet, 6.7 hours for the third sheet, and 7.0 hours for the fourth sheet.

[0011]

According to the method for manufacturing a wire saw of the present invention, the processing speed is faster than the fixing of abrasive grains by metal plating, and a long wire saw of 1,000 m or more can be easily manufactured in a short time. it can. In addition, since the binder of the abrasive grains is a synthetic resin, a cut surface with a good finish can be obtained when a brittle material such as a silicon ingot is cut. Further, since the binder of the abrasive grains is a synthetic resin, there is little possibility of disconnection due to fatigue of the binder.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of a method for manufacturing a wire saw according to the present invention.

FIG. 2 is an explanatory view of one embodiment of a wire saw manufactured by the method of the present invention.

FIG. 3 is an explanatory view of another embodiment of the wire saw manufactured by the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wire core material 2 Pulley 3 Pulley 4 Electrodeposition coating tank 5 1st washing tank 6 2nd washing tank 7 3rd washing tank 8 Heating furnace 9 Multi-groove pulley 10 Multi-groove pulley 11 Single wire 12 Synthetic resin film 13 Abrasive grain 14 Stranded wire

Claims (3)

[Claims] 1. A method for manufacturing a wire saw, comprising: attaching a synthetic resin and abrasive grains to a wire core material by an electrodeposition coating method; 2. A plurality of wire cores are run on a plurality of rotationally driven pulleys or multi-groove pulleys, and a synthetic resin and abrasive grains are attached to the plurality of running wire cores. A method for producing the wire saw described above. 3. The method for producing a wire saw according to claim 1, wherein the grain size of the abrasive grains is 50 μm or less, and the outermost diameter of the wire saw is 120 to 500 μm.